The recommended spaces to place the bottles of mosquitos with Wolbachia are those where there is no sunlight, and it is beyond the reach of children or pets. Honduras, August 2023. © Martín Cálix
Mosquitoes have four stages in their life cycle: egg, larvae, pupa, and adult. Here you can see hundreds of larvae that in the next few days will become adults to be released. Honduras, August 2023. © Martín Cálix
In Honduras, outbreaks are growing increasingly severe with more than 10,000 dengue cases reported each year. “Emergency thresholds are reaching alarming levels and current prevention methods fall short of protecting people from dengue,” says Edgard Boquin, Doctors Without Borders project coordinator in Honduras.
No specific treatments are currently available, and no vaccines have yet been produced that provide sufficient protection against infection. The use of outdated vector control techniques has also led to mosquitoes becoming resistant to current prevention methods and pesticide products.
With the aim of finding better and more sustainable solutions, Doctors Without Borders and its Honduran partners decided to trial prevention methods that have not been used in Honduras before, but that have proven effective in other countries with high levels of dengue. This includes releasing Aedes aegypti mosquitoes carrying the natural Wolbachia bacteria, which reduces mosquitoes’ ability to transmit arboviruses.
When the mosquitoes carry Wolbachia, the bacteria compete with viruses like dengue, making it harder for viruses to reproduce inside the mosquitoes. This means that mosquitoes are much less likely to spread viruses from person to person, reducing dengue fever in an area where Wolbachia is established in the local mosquito population.Claire Dorion, Technical Adviser
The World Mosquito Program’s Wolbachia method is safe for humans and the environment and has been successfully deployed in more than 12 countries, reaching some 10 million people. Evidence shows that virus transmission is significantly reduced in areas where Wolbachia is maintained at a high level.
Doctors Without Borders has been working closely with local communities to design, prepare and implement all activities, which will be carried out in 50 neighbourhoods in El Manchén health district, where some of the highest rates of mosquito-borne diseases are present in Tegucigalpa. Doctors Without Borders teams consulted with more than 10,000 community members in the area before starting activities. Ninety-seven per cent of people consulted support the plans, and many are actively involved in carrying out the mosquito release.
A Doctors Without Borders health promoter talks to a neighbor from the community to inform her about the release of mosquitoes with Wolbachia that we plan to carry out in this area of Tegucigalpa. Honduras, August 2023. © MSF/Maria Chavarria
Mosquitoes carrying Wolbachia will be released on a weekly basis for a period of six months. During a three-year period, tests will be carried out on the mosquito population to determine the percentage of Wolbachia mosquitoes.
In 2024, additional vector-control activities will be carried out in two other areas of the capital to reduce transmission inside people’s homes.
“The first objective is to reduce death and illness caused by dengue and other arboviruses. In the long term, we hope these new methods can become sustainable solutions to prevent people suffering from these illnesses," says Boquin.
“We have witnessed first-hand the challenges of implementing public policies and good vector-control practices to reduce dengue transmission in Honduras,” he says. “It is time for a change.”
